Remembering to remember: adult age differences in prospective memory.

Age-related differences in prospective memory were examined in a laboratory-based task in which younger and older adults performed different actions whenever a semantically defined target word occurred in the context of a free-association task. Requirements for self-initiated retrieval operations were manipulated by presenting target words that were typical or atypical instances (e.g., milk vs ink) of a given semantic category (liquid). The results showed that age differences in prospective memory were accentuated when atypical items were used as targets, but reduced when highly typical targets were presented. Furthermore, age differences were not limited to remembering when to perform action, but young subjects also showed better performance in remembering what was to be done. These findings indicate that the magnitude of age difference in prospective memory interacts with task complexity, and support the view that prospective memory failures are accentuated in tasks with high resource demands on self-initiated retrieval operations.